Is it an advantage to write in a foreign language? This month's literary sensation in France is Les Bienveillantes, a 900-page novel about the Holocaust, written in French by an American, Jonathan Littell. Littell, who lives in Spain, was partly brought up in France and claims to have written this, his first novel, in French because he worships Stendhal and Flaubert. The fact that he is adopting a "foreign" language seems to have increased the book's impact. French readers and reviewers speak of something unprecedented, something unlike the usual elegant, patterns of French fiction.

Writing in your second or third language is not unusual for great writers. The best-known example in English literature is probably Joseph Conrad, whose first language was Polish and second was French, but who wrote all his fiction (and even his diary) in English. Conrad (real name, Jósef Korzeniowski) claimed fatalistically that he did not choose English, rather: "It was I who was adopted by the genius of the language."

He also used to grumble that his choice brought mainly condescension. "I've been so cried up of late as a sort of freak, an amazing bloody foreigner writing in English." When he said this he was already author of some of the greatest English fiction, including Heart of Darkness.

Virginia Woolf recalled Conrad as "a foreigner, talking broken English", and even if his grammar was good his accent was sometimes impenetrable. Writing was a kind of liberation from the impossible demands of pronunciation. Others have also found creative freedom with an adopted language. Vladimir Nabokov, who like Conrad had English as a third language, switched from writing in Russian to writing in English on emigrating to the US. He became one of the greatest prose stylists of this foreign language, playing with its words as only a foreigner might.

Another modernist master, Samuel Beckett, has managed to make bilingualism seem a principle of his achievement, and some have said that his characters are always talking in a language foreign to them. Some of his most famous works - En Attendant Godot, Malone Meurt - were first written in French and only later translated into English by the author. For French fans he is French literature, though the great man's explanation for liking the language of his adopted country is characteristically double-edged: "En français, c'est plus facile d'écrire sans style [In French it is easier to write without style]."

When the German novelist Stefan Heym wrote his fiction first in English, before translating it into German, it made commercial sense: America was his first market. However, in time it became an intellectual principle, and even when he was living in East Germany and not being published in the west, he wrote first in English, as if this were the natural language of the dissident. This has its precedents. One of the greatest of French stylists, Voltaire, chose to write most of his Letters concerning the English Nation in English. He had spent a couple of years in London and come to regard England as the natural home of enlightenment. So he wanted to adopt his language too. And once upon a time all educated men (and the odd woman) wrote in a foreign language: Latin. Being clever was all about escaping your own silly tongue.